Undervoltage and overheating

Run vcgencmd get_throttled. Bits 0–3 describe active undervoltage, frequency capping, throttling and the soft temperature limit; bits 16–19 retain historical counterparts since boot. A historical flag alone does not mean an active fault. A reboot clearing history does not establish that an electrical cause was fixed.

For undervoltage, inspect the supply’s suitability, cable condition and length, connectors, peripheral power demand and stability under the actual workload. Software can report a condition but cannot repair a poor power source. Do not intentionally induce undervoltage to test alerts.

For high temperature, reduce optional workload and inspect airflow, heatsink contact and ambient conditions. Warning starts above 75°C for five minutes; critical above 80°C for two minutes. Verify firmware flags and actual temperature after the change. Do not invent fan RPM, PMIC temperature or wall power on unsupported hardware.

Record the observed flag transition and physical corrective action privately. Confirm active conditions clear and telemetry remains fresh, then verify recovery notification behavior.